Today more than 100 nations contain some 1,200 national parks or equivalent preserves. In the years following the establishment of Yellowstone, the United States authorized additional national parks and monuments, many of them carved from the federal lands of the West.

No, not every country has a designated national park, though most do. Several microstates and small island nations lack them due to their limited land area or highly urbanized environments. For example, Vatican City, the world's smallest country at just 0.17 square miles, consists entirely of religious and administrative buildings with no room for a park. Similarly, Monaco is almost entirely urbanized along the Mediterranean coast. Other countries without official national parks include San Marino, Bahrain, and Qatar, which may have nature preserves or protected marine zones but lack a unified national park framework. Singapore is another notable example; while it has extensive nature reserves and botanic gardens, it does not use the "national park" designation in the same way larger nations do. Additionally, countries suffering from long-term political instability or conflict, such as Somalia, often lack the formal environmental governance required to establish and maintain a national park system.